Inject user name and details to extractor

[minump]

Once user is logged in, pass on the user details to rct-extractor so that user details can be updated in the "Users" table in postgres db.

[minump]

The current frontend implementation is updating the users table with the display name of the user and updating the lastlogin field.
If the user name and details is passed to the rct-extractor, that can be used as dataset metadata and useful to know which user triggered the extractors. like here